Security Advisory - September 11, 2018

Zscaler, working with Microsoft through their MAPP program, has proactively deployed protection for the following 10 vulnerabilities included in the September 2018 Microsoft security bulletins. Zscaler will continue to monitor exploits associated with all vulnerabilities in the September release and deploy additional protections as necessary. 

CVE-2018-8367 – Chakra Scripting Engine Memory Corruption Vulnerability

Severity: Critical

Affected Software

• Microsoft Edge on Windows 10 for 32-bit Systems
• Microsoft Edge on Windows 10 for x64-based Systems
• Microsoft Edge on Windows Server 2016
• Microsoft Edge on Windows 10 Version 1607 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1607 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1703 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1703 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1709 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1709 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1803 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1803 for x64-based Systems
• ChakraCore

A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability.

The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.

CVE-2018-8391 – Scripting Engine Memory Corruption Vulnerability

Severity: Critical

Affected Software

• ChakraCore

A remote code execution vulnerability exists in the way that the ChakraCore scripting engine handles objects in memory. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user.

If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. The security update addresses the vulnerability by modifying how the ChakraCore scripting engine handles objects in memory.

CVE-2018-8420 – MS XML Remote Code Execution Vulnerability

Severity: Critical

Affected Software

• Windows 7 for 32-bit Systems Service Pack 1
• Windows 7 for x64-based Systems Service Pack 1
• Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)
• Windows Server 2008 R2 for Itanium-Based Systems Service Pack 1
• Windows Server 2008 R2 for x64-based Systems Service Pack 1
• Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)
• Windows Server 2012
• Windows Server 2012 (Server Core installation)
• Windows 8.1 for 32-bit systems
• Windows 8.1 for x64-based systems
• Windows Server 2012 R2
• Windows RT 8.1
• Windows Server 2012 R2 (Server Core installation)
• Windows 10 for 32-bit Systems
• Windows 10 for x64-based Systems
• Windows Server 2016
• Windows 10 Version 1607 for 32-bit Systems
• Windows 10 Version 1607 for x64-based Systems
• Windows Server 2016  (Server Core installation)
• Windows 10 Version 1703 for 32-bit Systems
• Windows 10 Version 1703 for x64-based Systems
• Windows 10 Version 1709 for 32-bit Systems
• Windows 10 Version 1709 for x64-based Systems
• Windows Server, version 1709  (Server Core Installation)
• Windows 10 Version 1803 for 32-bit Systems
• Windows 10 Version 1803 for x64-based Systems
• Windows Server, version 1803  (Server Core Installation)
• Windows Server 2008 for Itanium-Based Systems Service Pack 2
• Windows Server 2008 for 32-bit Systems Service Pack 2
• Windows Server 2008 for x64-based Systems Service Pack 2
• Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)

 A UAF vulnerability has been found in IE. This vulnerability can be exploited to achieve remote code execution.

CVE-2018-8440 – Windows ALPC Elevation of Privilege Vulnerability

Severity: Important

Affected Software

• Windows 7 for 32-bit Systems Service Pack 1
• Windows 7 for x64-based Systems Service Pack 1
• Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)
• Windows Server 2008 R2 for Itanium-Based Systems Service Pack 1
• Windows Server 2008 R2 for x64-based Systems Service Pack 1
• Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)
• Windows Server 2012
• Windows Server 2012 (Server Core installation)
• Windows 8.1 for 32-bit systems
• Windows 8.1 for x64-based systems
• Windows Server 2012 R2
• Windows RT 8.1
• Windows Server 2012 R2 (Server Core installation)
• Windows 10 for 32-bit Systems
• Windows 10 for x64-based Systems
• Windows Server 2016
• Windows 10 Version 1607 for 32-bit Systems
• Windows 10 Version 1607 for x64-based Systems
• Windows Server 2016  (Server Core installation)
• Windows 10 Version 1703 for 32-bit Systems
• Windows 10 Version 1703 for x64-based Systems
• Windows 10 Version 1709 for 32-bit Systems
• Windows 10 Version 1709 for x64-based Systems
• Windows Server, version 1709  (Server Core Installation)
• Windows 10 Version 1803 for 32-bit Systems
• Windows 10 Version 1803 for x64-based Systems
• Windows Server, version 1803  (Server Core Installation)
• Windows Server 2008 for Itanium-Based Systems Service Pack 2
• Windows Server 2008 for 32-bit Systems Service Pack 2
• Windows Server 2008 for x64-based Systems Service Pack 2
• Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)

An elevation of privilege vulnerability exists when Windows improperly handles calls to Advanced Local Procedure Call (ALPC).

An attacker who successfully exploited this vulnerability could run arbitrary code in the security context of the local system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and take control over an affected system.

The update addresses the vulnerability by correcting how Windows handles calls to ALPC.

CVE-2018-8447 – Internet Explorer Memory Corruption Vulnerability

Severity: Critical

Affected Software

• Internet Explorer 9 on Windows Server 2008 for 32-bit Systems Service Pack 2
• Internet Explorer 9 on Windows Server 2008 for x64-based Systems Service Pack 2
• Internet Explorer 11 on Windows 7 for 32-bit Systems Service Pack 1
• Internet Explorer 11 on Windows 7 for x64-based Systems Service Pack 1
• Internet Explorer 11 on Windows Server 2008 R2 for x64-based Systems Service Pack 1
• Internet Explorer 11 on Windows 8.1 for 32-bit systems
• Internet Explorer 11 on Windows 8.1 for x64-based systems
• Internet Explorer 11 on Windows Server 2012 R2
• Internet Explorer 11 on Windows RT 8.1
• Internet Explorer 11 on Windows 10 for 32-bit Systems
• Internet Explorer 11 on Windows 10 for x64-based Systems
• Internet Explorer 11 on Windows Server 2016
• Internet Explorer 11 on Windows 10 Version 1607 for 32-bit Systems
• Internet Explorer 11 on Windows 10 Version 1607 for x64-based Systems
• Internet Explorer 11 on Windows 10 Version 1703 for 32-bit Systems
• Internet Explorer 11 on Windows 10 Version 1703 for x64-based Systems
• Internet Explorer 11 on Windows 10 Version 1709 for 32-bit Systems
• Internet Explorer 11 on Windows 10 Version 1709 for x64-based Systems
• Internet Explorer 11 on Windows 10 Version 1803 for 32-bit Systems
• Internet Explorer 11 on Windows 10 Version 1803 for x64-based Systems
• Internet Explorer 10 on Windows Server 2012

A remote code execution vulnerability exists when Internet Explorer improperly accesses objects in memory. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, the attacker could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

An attacker could host a specially crafted website designed to exploit the vulnerability through Internet Explorer and then convince a user to view the website. The attacker could also take advantage of compromised websites, or websites that accept or host user-provided content or advertisements, by adding specially crafted content that could exploit the vulnerability. However, in all cases an attacker would have no way to force a user to view the attacker-controlled content. Instead, an attacker would have to convince a user to take action, typically by an enticement in an email or instant message, or by getting the user to open an attachment sent through email.

The security update addresses the vulnerability by modifying how Internet Explorer handles objects in memory.

CVE-2018-8459 – Scripting Engine Memory Corruption Vulnerability

Severity: Critical

Affected Software

• Microsoft Edge on Windows 10 Version 1803 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1803 for x64-based Systems
• ChakraCore

A remote code execution vulnerability exists in the way that the ChakraCore scripting engine handles objects in memory. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user.

If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

The security update addresses the vulnerability by modifying how the ChakraCore scripting engine handles objects in memory.

CVE-2018-8461 – Internet Explorer Memory Corruption Vulnerability

Severity: Critical

Affected Software

• Internet Explorer 11 on Windows 10 Version 1709 for 32-bit Systems
• Internet Explorer 11 on Windows 10 Version 1709 for x64-based Systems
• Internet Explorer 11 on Windows 10 Version 1803 for 32-bit Systems
• Internet Explorer 11 on Windows 10 Version 1803 for x64-based Systems

A remote code execution vulnerability exists when Internet Explorer improperly accesses objects in memory. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, the attacker could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

An attacker could host a specially crafted website designed to exploit the vulnerability through Internet Explorer and then convince a user to view the website. The attacker could also take advantage of compromised websites, or websites that accept or host user-provided content or advertisements, by adding specially crafted content that could exploit the vulnerability. However, in all cases an attacker would have no way to force a user to view the attacker-controlled content. Instead, an attacker would have to convince a user to take action, typically by an enticement in an email or instant message, or by getting the user to open an attachment sent through email.

The security update addresses the vulnerability by modifying how Internet Explorer handles objects in memory.

CVE-2018-8464 – Microsoft Edge PDF Remote Code Execution Vulnerability

Severity: Critical

Affected Software

• Microsoft Edge on Windows 10 for 32-bit Systems
• Microsoft Edge on Windows 10 for x64-based Systems
• Microsoft Edge on Windows Server 2016
• Microsoft Edge on Windows 10 Version 1607 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1607 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1703 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1703 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1709 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1709 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1803 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1803 for x64-based Systems

A remote code execution vulnerability exists when Microsoft Edge PDF Reader improperly handles objects in memory. The vulnerability could corrupt memory in such a way that enables an attacker to execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

To exploit the vulnerability, in a web-based attack scenario, an attacker could host a website that contains malicious PDF content. In addition, compromised websites and websites that accept, or host user-provided content could contain specially crafted PDF content that could exploit the vulnerability. However, in all cases an attacker would have no way to force a user to view the attacker-controlled content. Instead, an attacker would have to convince a user to take action. For example, an attacker could trick a user into clicking a link that takes the user to the attacker's site.

The security update addresses the vulnerability by modifying how Microsoft Edge PDF Reader handles objects in memory.

CVE-2018-8466 – Chakra Scripting Engine Memory Corruption Vulnerability

Severity: Critical

Affected Software

• Microsoft Edge on Windows 10 for 32-bit Systems
• Microsoft Edge on Windows 10 for x64-based Systems
• Microsoft Edge on Windows Server 2016
• Microsoft Edge on Windows 10 Version 1607 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1607 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1703 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1703 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1709 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1709 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1803 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1803 for x64-based Systems
• ChakraCore

A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability.

The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.

CVE-2018-8467 – Chakra Scripting Engine Memory Corruption Vulnerability

Severity: Critical

Affected Software

• Microsoft Edge on Windows 10 for 32-bit Systems
• Microsoft Edge on Windows 10 for x64-based Systems
• Microsoft Edge on Windows Server 2016
• Microsoft Edge on Windows 10 Version 1607 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1607 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1703 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1703 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1709 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1709 for x64-based Systems
• Microsoft Edge on Windows 10 Version 1803 for 32-bit Systems
• Microsoft Edge on Windows 10 Version 1803 for x64-based Systems
• ChakraCore

A remote code execution vulnerability exists in the way that the Chakra scripting engine handles objects in memory in Microsoft Edge. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability.

The security update addresses the vulnerability by modifying how the Chakra scripting engine handles objects in memory.